1. Field of the Invention
The field generally relates to vascular closure devices that use plugs, mechanical pressure, or sutures to close percutaneous openings of size 3-10 F. Specifically, the present device provides a means for simultaneously placing an ideal pattern of sutures in a vascular vessel that may be calcified to close openings such as 9-32 F without surgery now required to achieve this object.
2. Prior Art
3,470,875October 1969Johnson3,665,926May 1972Flores4,161,951July 1979Scanlon Jr.4,553,543November 1985Amarasinghe4,587,969May 1986Gillis4,744,364May1988Kensey4,852,568August 1989Kensey4,890,612January 1990Kensey4,929,246May 1990Sinofsky5,021,059June 1991Kensey, et al5,049,138September 1991Chevalier5,059,201October1991Asnis5,061,274October 1991Kensey5,087,263February 1992Li5,160,339November 1992Chen, et al5,163,946November 1992Li5,217,470June 1993Weston5,171,251December 1992Bregen, et al5,383,896Jan 1995Gershony5,411,481May 1995Allen, et al5,454,820October 1995Kammerer, et al5,454,821October 1995Harm, et al5,613,974Mar 25 1997Andreas et al5,728,109March 1998Shultz, et al5,769,862June 1998Kammerer, et al5,776,150July 1998Nolan, et al5,814,069September 1998Shultz, et al6,090,130Jul. 18, 2000Nash et al7,713,215May 11 2010Shriver7,771,422Aug. 10, 2010Shriver7,959,644Jun. 14, 2011Shriver
3. Devices and Procedures
Millions of percutaneous endovascular interventional procedures are performed each year to treat diseased coronary and peripheral arteries. The percutaneous method for entering arteries was described by Seldinger: the skin is punctured with a hollow needle pushed through a layer of subcutaneous adipose (fat) tissue to puncture an artery, usually the common femoral artery (CFA) in the groin. The angle of entry is generally between 40 degrees and 60 degrees. A guidewire is then advanced through the hollow needle to enter the artery lumen. The hollow needle is withdrawn and an introducer sheath advanced over the guidewire into the opening, thus forcing the opening to the size of the sheath. Introducer sheath has proximal end outside the body and distal end inside the artery lumen and a circumference large enough to introduce the size of tools and graft materials needed for the intended procedure on arteries of the heart or peripheral to the heart, e.g. in legs or neck. The opening forced by the sheath splits the artery from side to side rather than along the longitudinal axis. Since openings in the body are not perfect circles the French measurement system approximates the circumference of the opening's free edge in mm by expressing diameter in units that are ⅓ mm. Thus an opening, sheath, or catheter that is 1 French (1 F) is ⅓rd mm in diameter and approximately 1 mm in circumference, and 3 F is 1 mm in diameter and about 3 mm (an approximation of 3.14 mm) in circumference. Fluid pressure in the introducer sheath is maintained at a level that prevents blood pressure in the artery from causing blood to flow from the artery through the opening. When the procedure is finished tools and sheath must be removed and the opening closed.
The Seldinger method of closing is used for small openings such as 3 F. Pressure is applied manually on the skin opposite the opening after removing the sheath. The manual pressure must be greater than the blood pressure within the artery in order to maintain hemostasis while the natural elasticity of the blood vessel wall reduces the size of the opening until, after sufficient reduction, a blood dot forms to finally close the opening. The natural recoil of the vessel wall free edge around the opening might require 15 minutes of manual pressure for a 3 F opening but hours for an opening such as 6-8 F. And in older people the elasticity of vessel wall is less and thus recoil takes longer. Disadvantages of the pressure method include time and discomfort of patient but the advantage is minimal complications. Thus manual pressure is still the gold standard for access site management but the disadvantage of time required to ambulation has led to the evolution of many alternatives. None of these alternatives apply to openings larger than 8 F as the present invention does, so this background is only generally relevant to the present invention.
Mechanical Pressure
A certain type of device applies mechanical pressure to reduce the size of a larger opening to a smaller opening that can finally be closed by manual pressure. This type of device requires manual pressure to make the final closure because a wire or tube remains in the path left by the sheath when it was removed and the opening cannot close until it is removed. These devices are not intended for use with openings larger than 6-8 F. Gershony in U.S. Pat. No. 5,383,896 reveals a balloon on a tube that is preferably not greater than 0.038 inches in outside diameter. The tube is advanced through the sheath so the balloon on the distal end can be inflated in the artery lumen. The balloon is pre-selected to be larger than the opening so it blocks blood and maintains hemostasis after the sheath is removed. A relatively large diameter fixation collar is located on the proximal end of the tube (shaft) and pressed against the skin opposite the opening to allow its place to be secure within the blood vessel. Another device for applying mechanical pressure is available under the commercial name Boomerang™. It utilizes site-specific compression, similar to that of the Gershony device. But instead of a balloon in the vessel lumen, this device has a collapsible wire mesh disc on the end of a wire. The collapsed disc is pushed through the sheath by the wire and adjusted into a flat disc inside the lumen. The flat wire disc is larger than the opening but is somewhat porous so does not seal the opening to achieve hemostasis. Hemostasis is achieved after the sheath is removed by clipping a detent on the wire against the skin where manual pressure is normally applied. The pressure can be adjusted by moving the detent more firmly against the skin—as manual pressure from a finger would be applied. This may be done in the cath lab in less than a minute to produce hemostasis. The patient can then be moved from the cath lab with the device in place. The opening relaxes around the wire by the natural process of elastic recoil while normal clotting mechanisms begin. The natural elastic recoil of the vessel wall occurs unless the patient's artery has lost so much elasticity that it does not fully recoil. When the size of the opening has reduced to the size of the wire, the wire disc is collapsed and the device removed. Normal manual pressure is then applied to close the remaining opening left by the removed wire.
Sealants/Plugs
There are a number of patented vascular closure devices (VCD) for placing a sealant or plug in the opening or in adjacent fat tissue with some success in the market. The invention revealed by Kensey in 4890612 describes the type of device that creates a plug for the opening. A relatively hard anchor disc is attached to a filament (string) introduced through an elongated tube with a plunger. This places the anchor disc in the artery lumen and the string is used to pull the plug against the opening while a biodegradable gel foam or collagen is pushed through the tube to surround the string and fill the opening. This maintains hemostasis and the plug biodegrades within a month or two. This device is handicapped by two properties inherent to the technology. First, the anchor placed inside is occasionally obstructive, either at the puncture site or with embolization. Second, it leaves a mass of collagen inside the tissue track and a filament (string) that extends from the arteriotomy to near the skin surface, which provides both a nidus and a wick for potential infection. There are other devices for placing plugs of this type without a string, e.g. Angio-Seal, a commercial device similar to the Kensey device still leaves a thrombosing agent in the tissue track. Another plug-type device uses a balloon as an alternative form of anchor disc. The balloon is opened in the lumen and held against the opening while the biodegradable seal substance is injected to plug the opening. There are also various patches to place on the skin and chemical gels applied under the skin to counteract the effects of anticoagulants used during many percutaneous procedures to prevent clotting. These must be reversed when clotting is needed to close the opening. There are several reasons these VCDs have not displaced the simple pressure method to meet the need for a rapid, safe, and reliable hemostasis. They have not clearly been shown to reduce the incidence of bleeding, vascular complications or cost when compared with traditional compression but have been successful in decreasing time to ambulation. Obese patients are among the best candidates for these alternatives because direct pressure on the skin of an obese person may be transmitted laterally through fat layers and away from the opening, thus providing insufficient pressure at the vessel. These devices are used for closing openings up to 6 F.
Staples/Clips
Another type of closure device uses staples or clips to close the opening. The device called Starclose® advances a ring of barbs through the sheath and into the edge around the opening. The barbs are then turned inward to clip together the edge and thus close the opening. No manual compression is needed after using this device as it closes small openings completely. This device is not intended for use with large openings, there is relatively little experience with it and it is not in common use.
Intravascular Sutures
During the few minutes a suture is being placed, blood is stopped from flowing in the artery by applying pressure on the skin opposite. After a suture closes the opening, the suture provides hemostasis; there is no requirement for further pressure, sealants or lengthy time to ambulation. Other types of devices for maintaining hemostasis without sutures were briefly reviewed as general background. But there is only one device for closing percutaneous openings by a suture and it places one suture. It is based on U.S. Pat. No. 5,613,974 of Mar. 25, 1997 by Andreas et al, which is assigned to Perclose®, now owned by Abbott labs, and describes a type of intravascular suture closure device approved for placing one suture in an opening up to 8 F. That invention and those prior to it are included as potential prior art for the present invention of an intravascular suturing device that places a plurality of sutures in a particular ideal pattern. A common femoral artery is about 1 mm thick at an opening made for percutaneous procedures and an opening of 8 F is a little more than 8 mm in circumference. The free edge of that circumference folds to a slit of a about half the circumference, or 4+ mm. Placing one suture across the free edge leaves about 2 mm on each side. When a surgeon has free access to place sutures, he/she will place the needle at a distance from the free edge that is equal to the thickness of the artery and place successive sutures twice this distance apart. Thus the Perclose device does this for openings up to 8 mm in circumference of 8 F, and that is the largest opening for which the device is approved for use.
Ideal Spacing of Sutures
The ideal spacing of sutures is 2 mm between sutures and 2 mm across free edge for an artery with wall thickness of 1 mm. Thus two sutures in the ideal pattern will close a slit of 6 mm (2 mm on each side and 2 mm between 2 sutures), 3 sutures will be required for a 8 mm slit, 4 for a 10 mm slit, 5 for a 12 mm, etc. A 24 F opening is about 24 mm in circumference so closes to a 12 mm slit that require 5 sutures 2 mm apart. The suturing pattern described as “ideal” is the result of numerous studies with animals and practice with human patients. There is a tendency for the lumen to be reduced along the line of suture across the artery. This reduction can be avoided by placing sutures 2 mm apart and 1 mm from the free edges of the slit with vessel wall thickness of 1 mm. This creates a slight increase in mass of tissue edges in opposition across each suture that exerts lateral pressure that counteracts the tendency to constrict the lumen, thus producing a curved line of sutures matching the original curvature of the vessel. This curved line of sutures is called a two-by-two as each puncture site is 2 mm from the one opposite it across the free edge and 2 mm from the adjacent. For a vein with thinner wall the distances should be closer to 3 by 3 mm. Vessel walls vary in both thickness and diameter among individuals but on average common femoral arteries (the usual site of percutaneous entry) are about 1 mm thick and about 7 to 11 mm in diameter, making artery circumference range from about 22 mm to 33 mm.
Larger Openings Required
There are procedures requiring openings of 24 F or even larger, e.g. aneurysms of the larger arteries of the legs such as abdominal aortic arch and of carotid arteries. Cut down for a surgeon to place sutures to close large opening has traditionally been used after these procedures so the surgeon can apply the ideal number and spacing of sutures manually. However open surgery has its own disadvantages and risks, so some exceptions are made to allow off-label use of a Prostar XL® device or two Perclose® devices to make a “purse-string” closure of the opening, pulling four points on the edge of the opening to the center and thus producing a closure that is not ideal, is technically difficult to perform, has some complications, and is usable only under certain conditions. Making the appropriate knot to tie suture ends also requires considerable skill and time so if alternative means can be invented to join suture ends by a faster, safer way than tying a knot in each, that would be an added advantage. Thus “off-label” is a workable solution for highly skilled practitioners but not a satisfactory long-term general solution for routinely closing large openings.
Device Characteristics for Meeting Future Needs
In addition to procedures that now require large openings, there are new procedures for replacing heart valves through large percutaneous openings, such as 24 F. These require highly skilled practitioners now but if they are to become generally usable a better means than off-label use of devices will be needed. And if devices for placing bypass grafts around occluded arteries of the heart and legs are to replace the less effective angioplasty devices that use balloons and stents, an effective, safe and easily performed means of closing the required large openings will be required. An approved device for closing larger openings by sutures that meet the ideal spacing criterion of surgically placed sutures would be preferred over a purse string pattern. Another problem of placing sutures in arteries is that they are frequently calcified making it difficult to push a suturing needle through the vessel wall even when the surgeon can manually access the artery. If a device can provide means for pushing needles through calcified arteries more effectively than a surgeon can manually, that would be still another advantage. And if sutures can be placed simultaneously rather than sequentially as required with manual suturing and other devices, that is another major advantage by reducing time to perform. If the new device were to use pre-tied knots it would eliminate a difficult step reducing both the time and skill required. The availability of a device with any or all of these desired characteristics could be an important determinant of what type of other devices become practical for accomplishing future procedures such as transcatheter aortic valve implantation and transcatheter bypass graft placement. The present invention is expected to have all these advantages with its initial application being to closing large openings in common femoral arteries after completion of a percutaneous procedure requiring a large opening. It also applies to other vessels such as veins and even to skin, but the example used will be an artery in order to simplify the discussion. The device is designed as a means of placing sutures in the ideal 2×2 pattern in a curved line, provide means for penetrating calcified arteries with greater ease than a surgeon can achieve manually, place all sutures simultaneously with easily performed steps, and provide a quickly applied simple alternative to manual knot tying each knot individually and cutting all ends at opening simultaneously.
Advantages
1. Millions of procedures are performed each year that require percutaneous openings of 3-6 F. Manual pressure is commonly used for closing openings of 3 F and there are numerous devices for closing openings up to 6 F, generally by plugging the opening with substances that are foreign to the body and thus not desirable. There are two devices for closing opening up to 8-10 F by placing one or two sutures in a cross pattern to make a purse string closure which has disadvantages with respect to ideal suture closures made with open surgery.2. The Perclose® device is approved for placing one suture to close opening up to 8 F. The Prostar XL® device is approved for placing two sutures in a cross pattern for a purse string closure of openings up to 8-10 F. Open surgery places any number of sutures in the ideal pattern of 2×2 to close openings of 24 F or even larger, but has the disadvantage of more risk and greater trauma have devices for closing openings percutaneously.3. The only currently approved means of closing openings of 11 to 24 F is with sutures manually placed by a surgeon, and this is done in the ideal configuration of sutures being 2 mm apart and 2 mm across the free edge of the slit produced by drawing the opening to half its circumference. It is called 2×2 and is ideal because it produces a curved line of sutures that matches the original vessel shape thus not narrowing the vessel. For veins of less than 1 mm thickness a distance of 3 mm apart and 3 mm across free edge is ideal, and called 3×3. There are increasing numbers of procedures that require larger openings and no device is approved for percutaneously closing openings larger than 8-10 F.4. To avoid the risks and debilitation of open surgery for closing openings larger than 10 F, physicians sometimes use one Prostar XL® device with an unapproved technique or two Perclose® devices, also off-label, to place two sutures in a cross pattern thus making purse string closures of openings up to 24 F—or even larger. This off label use of devices is technically difficult, does not prevent narrowing the vessel, is done only under restricted conditions, and has other complications, so cannot be long-term solutions for closing openings larger than 8-10 F.5. The intravascular suturing device described and claimed herein is appropriate for percutaneously closing openings of 6-33 F with the ideal configuration of 2 to 7 sutures in a curved line that avoids narrowing the vessel. Thus the device avoids the risks of surgery while achieving the ideal suturing configuration and has other important advantages.6. The device claimed herein places sutures simultaneously rather than sequentially. A skilled surgeon requires more than a minute to place one suture, or about the time required by the device to place all sutures. The other devices require even more than a minute to place each of two sutures in a cross pattern.7. Another problem with placing sutures is the skill and time required to tie the ends of each suture with a special knot, run them individually to vessel wall and cut each with a special tool. The present intravascular suturing device provides preformed knots or clips to secure suture ends, runs knots to vessel wall and cuts knot ends at vessel wall simultaneously.8. Still another problem with placing sutures is that arteries and veins are frequently calcified making it difficult to push a suturing needle through the wall and the wall stretches in the direction of applied needle force. The surgeon can't place a finger in front of the needle to prevent the stretching and has no other means of counteracting this tendency. The present device provides a needle housing outside the calcified vessel wall opposite the needle nose inside the vessel wall and they are forced together with the force of an inclined plane thereby piercing the calcified vessel wall between.9. The advantages of this device are that it does not require surgery, closes large openings that other vascular closure devices cannot close or close less effectively, places sutures simultaneously in less time than other means and accomplishes this in calcified or non-calcified vessels in less time, more effectively and without the risks of manual suturing.
Key1.Center board2.Suture placement component3.Threaded post4.Separator wire5.Separator wire channel6.Short snare groove7.Overlap8.Slot stopper9.Loops and hooks10.Needle nose11.Needle shaft12.Friction dowel13.Frame14.Suture end15.Suture loop16.Suture cove17.Guidewire channel18.Cove wall19.Outboard20.Foot21.Needle nose housing22.Surround23.Access slot24.Balloon25.Screw turner26.Spring clip27.Housing detent28.Vessel wall29.Free edge slit side30.Free edge slit across31.Spur32.Female threads33.Cross wire34.Cross slot35.Blunt end36.Suture compartment37.Bridge wire38.Fluid channel39.Proximal port40.Needle opening41.Wedge end42.Keeper43.Stopper44.Needle pair45.Nose indent46.Distal port47.Outboard legs48.Guidewire49.Blockhead50.Split blockhead51.Unthreaded hole52.Cross clamp53.Crossbar54.Scissors cutter55.Strip holder56.Female strip57.Male strip58.Suture shield59.Tension adjustor60.Slant end rod61.Release rod62.Slant channel63.Release channel64.Friction pad65.Hinge66.Clasp67.Clasp button68.Fluid port proximal69.Recessed area70.Barbs71.Tongue and groove72.Centerboard slot73.Frame slot74.Break away strip75.Holder slot76.Compression breaker77.Fluid port distal78.Fluid port edge79.Knot leader80.Slip knot81.Foot loop82.Long applicator83.Knot rod holder84.Wire snare85.Snare tightener86.Spring roller87.Knot rods88.Short applicator89.Cutter end90.Cutter pusher91.Push knob92.Snare holder93.Applicator nose94.Knot rod channels95.Resistance film96.Rail leader board97.Suture slots98.Loop leader board99.Tightener gate100.Snare detent101.Pinch sleeve102.Cutter channel103.Suture tying component104.Suture clip component